Dial impulse register



p 1960 ZENICHI KIYASU l-n-AL 2,952,742

DIAL IMPULSE REGISTER ll Sheets-Sheet 1 Filed May 31, 1956 '/Z PHA UM SA SAAM& A L omANoo w T UN A mm m Vm A WNS IU EOUHR ZK mA I UU SB UOW.SNT U Sept. 13, 1960 ZENlCHl KlYASU ETAL 2,952,742

DIAL IMPULSE. REGISTER Filed May 31, 1956 11 Sheets-Sheet 2 ,'g 2Q x x Jg Z flgzflll 1 11 I[[' I llllHll llHlllH 111mm H HH IIIHIII Hmm I IllHlllllll mmm m: H mm! mum w m lllHllll lHlHlH lllllHll mum m m IH'IIYIAtt s.

Sept. 13, 1960 ZENlCHl KIYASU ETAL 2,952,742

DIAL IMPULSE REGISTER Filed May 31, 1956 ll Sheets-Sheet 3 INVENTORSZENICHI KIYASU. KOSHIRO HANAWA. SUSUMU KATSUNUMA. NOBUICHI IKENO &TAKEHARU FUKUOKA VIWfKJ WM Sept. 13, 1960 ZENlCHl KIYASU EIAL 2,952,742

DIAL IMPULSE REGISTER Filed May 31, 1956 ll Sheets-sheet 4 'g- 4 Id dDIAL cu/r/rmr 4 INVENTORS ZENICHI KIYASU. KOSHIRO HANAWA, SUSUMUKATSUNUMA. NOBUICHI JKENO 8. TAKEHARU FUKUOKA Sept. 13, 1960 ZENICHIKIYASU ETAL I 2,952,742

DIAL IMPULSE REGISTER Filed lay 31, 1956 11 Sheets-Sheet 5 NOBUICHI NO&,

TAKEHARU FUKUOKA BY 7142M, \(PM At y Sept. 13, 1960 Filed May 31, 1956ZENICHI KIYASU ETAL 2,952,742 DIAL IMPULSE REGISTER ll Sheets-Sheet 6 ]IIII I II III a Q Q m7 0; M9

INVEN TORS ZENICHI KIYASU,

KOSHIRO HANA WA, SUSUMU KATSUNUMA' NOBUICHI IKENO8- TAKEHARU FUKUOKASept. 13, 1960 ZENICHI KIYASU ETAL DIAL IMPULSE REGISTER ll Sheets-Sheet7 Filed May 31, 1956 mvznrons ZENICHI KIYASU. KosmRo HANAWA. susuuuKATSUNUMA. uoawcm -|KNO a, TAKEHARU FUKUOKA Y v fwafiu w Sept. 13, 1960ZENlCHI KIYASU ETAL DIAL IMPULSE REGISTER ll Sheets-Sheet 8 Filed May31. 1956 A MM 0 K wm u Fmfi A U I R A H E M T Y B Sept. 13, 1960 ZENICHIKIYASU ETAL "I 2,952,742

DIAL IMPULSE REGISTER Filed May 51, 1956 11 Sheets-Sheet 9 ZENICHI K!YAS U. KOSHIR O HANAWA,

SUSUMU KATSUNUMA, NOBUlC HI IKENO & TAKEHARU FUKUOKA BY WM, AttJS.

Sept. 13, 1960 ZENICHI KIYASU ET AL DIAL IMPULSE REGISTER Filed May 31.1956 ll Sheets-Sheet 10 fig-7 INVENTOR'S ZENICHI KIYASU. KOSHIRO HANAWA,SUSUMU KATSUNUMA. NOBUICHI IK'ENO8. TAKEHARU FUKUOKA WM, 2:}. 1 $0MUnited States Patent Office DIAL IMPULSE REGISTER Zenichi Kiyasu,Koshiro 'Hanawa, Susnmu Katsunuma, Nobuichi Ikeno, and Takeharu Fukuoka,Tokyo, Japan, assignors to Nippon Telegraph & Telephone PublicCorporation, Tokyo, Japan, a corporation of Japan Filed May 31, 1956,Ser. No. 588,407

7 Claims. (Cl. 179-18) This invention relates to a dial impulseregister, and more particularly to a dial impulse register in whichparametrically excited resonators are used as unit operating elementsthereof.

It has hitherto been the practice to register the subscribers dialimpulses by relay devices or mechanical devices, in cross-bar or othertelephone exchange systems. However, the cross-bar switching systemrequires many relays and therefore is expensive. Other mechanicalsystems are defective in that the sliding parts thereof are easily worn,and the flexible parts thereof are easily damaged, and the adjustmentthereof is difi'icult. Furthermore, in view of the present-dayspeeding-up of the common control parts thereof, the above systems areconsidered to be already at their maximum operating speed.

One object of the present invention is to provide a dial impulseregister, in which the operating elements thereof make no movement,whereby such operating elements will not be worn or damaged. The dialimpulse register according to the invention therefore has a much longerlife than the known dial impulse registers.

Another object of the present invention is to provide a dial impulseregister which has a high operating speed, and. in which a dial having ahigher dial-speed or a larger dial speed variation than the known dials,may be used.

In order to accomplish the above objects, there are used parametricallyexcited resonators, formed by nonlinear reactance elements, as unitoperating elements of the dial impulse register, and to count and storethe dial impulses by electric circuits which are formed by a combinationof such resonators. Such resonators are composed of electric elementswhich make no movement, and have no practical limitation of their life,in which property they differ from the electronic elements such asvacuum tubes and discharge tubes, in which the thermionic emission isdecreased during normal life.

The accompanyingdrawings show for the purpose of exemplification,without limiting the invention or claims thereto, certain practicalembodiments illustrating the principles of the invention wherein:

Figs. la-d and 2a-g are circuit diagrams and symbols for explaining theoperating principle of parametrically excited resonators.

Figs. 3a and b are the circuits for converting the dial current intohigh frequency current having two kinds of phase-states.

Fig. 4 is a circuit for generating timing signals, necessary formeasuring make and break periods of dial current, together with a blockdiagram of the converting circuit of Figs. 3a and b.

Fig. 5 is a circuit diagram for detecting the interdigital pause.

Fig. 6 is a circuit for counting impulses.

Fig. 7 is a circuit for counting a number of decimal digits.

Fig. 8 is a circuit for storing the number of impulses Patented Sept.13, 1960 counted, namely registering the oflice number and the calledsubscribers number.

Fig. 9 is a connecting line between the circuits of Figs. 7 and 8.

Fig. 10 is a diagram showing how the circuits of Figs. 4 to 9 can becombined together.

Figs. 11 and 12 are other embodiments of the counting circuits.

We shall explain hereunder the construction and the performance of aparametrically excited resonator, the unit operating element of thepresent invention. In the resonance circuit of Fig. In, L is a magneticcore, such as a ferrite core, having coils thereon, C is a capacitor,and R is a resistor. A high frequency current having a small amplitudeand frequency f (for example, 1 me.) is applied to the terminal 3 of theabove resonance circuit, and then a curernt having frequency 2 and acomparatively large amplitude (hereinafter called the exciting current)is applied to the terminals 1 and 2. An oscillating current havingfrequency 7, half of the exciting current, is produced in the resonancecircuit. This phenomenon is caused by the periodic variation at 2 of theinductance in the resonance circuit due to the excitation by the currentof frequency 2 and the phenomenon can be explained mathematically by thesolution of Hills equation or Mathieus equation, if the current which isproduced in the resonator is small (see E. T. Whittaker and G. N.Watson: A Course of Modern Analysis, pp; 404-428, Cambridge Univ., 1935.In actual practice, the magnetic cores have considerable saturationcharacteristics, and therefore, the oscillation produced is not sosimple as Mathieus solution. However, the essential oscillation is quitethe same. Due to the saturation characteristics of magnetic cores, theabove oscillating current produced in the resonance circuit reaches asteady state having a constant amplitude. The phase of the oscillatingcurrent, produced in the resonance circuit, is limited to either of thetwo phases, difierent from each other by 7r radians, as shown in Fig.1b. Which of the two phases the oscilalting current takes depends uponthe initial condition, namely, the phase of the high frequency currentapplied from the terminal 3 to the resonance circuit. However, theoscilaltion phase is always either one of the two phases, different fromeach other by 71' radians. We shall hereinafter refer to these twophases as 0 phase and 1r phase respectively as shown in the drawings, orsimply as 0 and 1, in logical representation.

In Fig. 1a, the windings between the terminals 1 and 2 are balanced sothat the voltage induced in the resonance circuit by the excitingcurrent will be cancelled, and the exciting current having frequency 2applied at the terminals 1 and. 2 does not appear in the resonancecircuit. A gain of scores of decibels can be obtained between theoscillating current having frequency 1 produced in the resonance.circuit andthe current applied to the terminal 3. This is of advantagein making circuit connections in cascade. or in branches, without usingamplifiers composed of vacuum tubes or transistors.

Fig. 1c shows the case in which there are provided three inputterminals, 3, 4 and 5, instead of the single terminal 3 in Fig. 1a. Inthis case, it will be clearly understood that the phase of theoscillating current produced in the resonance circuit, after theimpression of exciting current, is determined by the phase of thesuperposed current of the three currents, which are applied to theterminals3, 4-and 5. Therefore, the phase of the oscillating current inthe resonance circuit is as shown in the- Table I, depending upon thephases (ll-phase or 1r-phase) of the three high frequency currentshaving equal amplitude and appliedto the terminals 3, 4 and 5.

Table II represents such and rr-PhflSBS replaced by logical signs, 0 and1 respectively. By fixing the phase to be applied to the terminal 3 as0-phase or rr-phase, a logical product circuit (hereinafter referred toas AND and shown as 6) and a logical sum circuit (hereinafter referredto as OR and shown as 69), of which the input is applied from theterminals 4 and 5, are respectively formed, and the output thereof canbe taken out fi'om the terminal 6.

TABLE II f p R in Figs. 1a and c is a coupling resistor of the input oroutput of the resonance circuit. However, instead of such resistor, anelement with any impedance or a transformer may be used for the couplingelement. Fig. 1d

shows an example of the transformer coupling. A single turn issufficient as a primary winding of the transformer T, when the frequencyis about 1 me. This makes the connections much simpler, and also makesthe phase reversal (logically, it means NOT) simpler, it being necessaryonly to reverse the direction of the turn wound on the magnetic core.The resistors R in Fig. 1d are so selected that the transmission lossbetween two resonance circuits in adjoining stages will be about 30-40db and that the producing and damping period of oscillation will besuitable. The unit elements formed by magnetic cores, capacitors, andresistors, shown in Figs. 1a, 0 and d are hereinafter referred to asparametrically excited resonators or parametrons, and the symbols inFig. 2 shows such parametrons and their logical functions. Namely, Fig.2a shows a single parametron; Figs. 2b and 0 show respectivelyparametrons having an AN function and OR function; and Figs. 20?, e andshow the connection of a plurality of parametrons. In the drawings, thecross on the line connecting the two parametrons shows the phasereversal NOT. I, H and HI appearing in Figs. 2d, 2 and 1 show theexcitation periods of the corresponding parametrons, and the threeexcitationperiods are made to overlap each other slightly in relation totime, as shown in Fig. 2g. By such excitations, the logical operationprogresses following the order, III, II-III, and IIII. In the drawings,it is assumed that the logical operation normally progresses to theright. The back coupling to the left is specially marked by an arrow.

InFig. 3a, coils, L and U wound on the non-linear core, D and coils Land L wound on the non-linear core D are connected in a modified latticeform, L and L' having the same number of turns, L and L' having the samenumber of turns, and the number of turns of the former two being onemore than that of the latter two. Therefore, the inductance of coils, Land U is larger than that of L and L' and the phase of current at theoutput terminals 3 and 4 is in phase with that of the current at theinput terminals 1 and 2. However, when a direct current flows in anothercoil L wound on the core D the inductance of coils L and U decreases andbecomes smaller than that of coils L and U due to the non-linearsaturation characteristics of the core D and the phase of the current atoutput terminals 3 and 4 becomes in opposite to that of the currentat'the input terminals 1 and 2. By connecting the two parametrons 7 and9 with the above circuit, the parame- 4 tron 9 oscillates at a 0-phasestate and a rr-phase state in response to the break and make of the dialcontact of the subscribers telephone if the signal of parametron 7 isfixed as O-phase.

In Fig. 312, P and P show two parametrons which are coupled by resistorsR1, R and a transformer T. In this case, P and P are coupled in oppositephase relation by resistor R transformer T, capacitor C, rectifier G andthe earth, on the one hand, and are coupled in the same phaserelationship by resistor R transformer T and ground, on the other hand.When the direct current does not flow in the rectifier G, the resistanceof G is high, and the signal transmitted from P to P through thecircuit, R T-CGground, is weaker than the signal transmitted from P to Pthrough the circuit, R T. Therefore, P and P oscillate with the samephase. When a contact is made at the subscribers phone, a negativedirect current of about 1 m.a. flows through the circuit, battery(48v.)-resistor R -telephone contact-resistor R G. Then the resistance of Gis lowered by scores of ohms. As the result thereof, the signal from Pto P through R --TCG,-ground becomes more intense than the signalthrough R -T, and P is oscillated in with a phase opposite to the phaseof P In this way, parametron P can be made to oscillate at O-phase stateand vr-phase state, in response to the break and make of the currentcaused by a subscribers dialing.

In Fig. 4, the oscillation phase of the parametron elements 11, 12 and13 is cyclically reversed from 0 to 1r or vice versa, during everyperiod of one cycle of excitation III-III. Assuming that 11 oscillatesat 0- phase during the exciting period III, 12 oscillates at 0- phaseduring the following exciting period 1, due to the in-phase couplingfrom 11. During the following exciting period II, 13 oscillates atvr-phase, due to the reverse coupling from 12. During the followingexciting period III, 11 oscillates at 1r-phase, the same as 16. Duringthe following exciting period I, 12 oscillates at rr-phase. During thefollowing exciting period II, 13 oscillates at O-phase. It is clearthat, in this Way, the oscillation phase respectively of 11, 12 and 13is reversed at every cycle ,of excitation I]I-III. The signalalternately produced is applied from the element 11 to the elements 14and 17. The circuits which follow, 1415.16; 18-19 20; 424344respectively form loops. The oscillation phase of 14 is not changed whenthe signal from 11 is 0. However, when the signal from 11 is changedinto 1, because 14 is an OR element, the phase of 14 is changed into 1.This signal cycles to 15 and 16, and this state is sustained even whenthe phase of 11 is returned to 0. In this case, the phase of -17 staysas 0, because 17 is an AND element, and unless the phases of 11 and 16become simultaneously 1, the phase of 17 does not become 1. Then, whenthe phase of 11 is again changed to 1, the AND element 17 becomes 1 forthe first time. And when the above signal 1 of the element 17 is appliedto 18 and 21, the AND element 15 returns to 0, due to the NOT signal 0applied to 15, and 16 and 14 are also changed into 0. Namely, whenever.the loop 14--1516 receives the phase 1 from 11, the

phase of this loop becomes alternately 0 and 1. In other words, at everytwo applications of the signal from 11, the signal 1 is produced at 17.The operation of the next loop, 1819-20 is quite similar. On applicationof the signal 1 at 17, the phase of the loop, 181920, is alternatelychanged into 0 and 1. At the element 21, the signal 1 is produced atevery four occurrences of the signal 1 at 11. The operations of thefollowing loops,

22-23-24, 26-2728, 4243-44 are also similar. Namely, the signal 1 isproduced at the element 25 at every eight occurrences of the signal 1 at11, at the element 29 at every sixteen occurrences of the signal 1 at 11at the element 45 at every two hundred fifty-six occurrences of thesignal 1 at 11. The element 5 11 produces the signal and 1 alternately,and therefore, assuming that the duration of exciting period 1, 11 andIII is respectively 0.025 milli second '(ms.), the signal 1 is producedat 11 at every 0.05 milli second, and the signal 1 is produced a 45 atevery 12.8 milli seconds, the duration of such signal being 0.025 millisecond.

The value 12.8 ms. has been selected from the permissible range of thespeed of dialing.

The signal output of the element 45 is applied to the elements 101, 106and 111 in Fig. 5, through the lead 0, as a timing signal. The timingcircuit of Fig. 4 can be used in common with other registers. The signalcoverted by the circuit of Fig. 3, represented by box 8 and parametrons'7 and 9 in Pig. 4, is transmitted to the elements 101 and 106 throughlead shown in the block diagram in the upper part of Fig. 4.

In Fig. 5, the converted dial impulse signals, which are transmittedfrom the element 9 to the'elements 101 and 106, are sampled by thetiming signal which appears from the element 45 at every 12.8 ms. Whenthe converted dial signal is -0 (corresponding to a break), the signal 1appears at the element 101 at-the application of :the timing'signal withphase 1 thereto. When the converted dial signal is 1 (corresponding to amake), the signal 1 appears at the element 106 at the application of thetiming signal with phase 1 thereto. When the .signal of the element 101is -l, and if the signal of the loop, '1-03-104 105, was 1 during theperiod prior to the period at which the element 101 has a phase 1, theAND element 102 becomes 1, and this signal 1 is applied to the element.105 and causes the element 105 to become 0 which in turn causes loop'103104105 to become 0. When the dial signal has a phase 1 during thenext timing period, the element 106 assumes a phase 1 and the phase 1appears at the element 107 which changes the phase of 103104-105 into 1.Thus the loop 103104105 (the operation of which has been represented asthat of 103) quantizes the make and break of the subscribers dialcurrent and indicates the same as a signal in the form of a phase. Suchquantizing accomplished by the above circuit is for avoidingmiscounting, caused by the distortion of the duration of the makecurrent and the break current which is due to the inductance andcapacitance of the subscribers line and also by thesirnulated impulsewhich is due to chattering of contacts occurring in dial mechanisms.Since-theperiod of the timing signal is 12.8ms. in the device of thisinvention,a-correct counting can be made, without being influenced bya-simulated impulse or by an irregular break having a duration less than12.8 ms. The elements 102 and 107 produce-signal 1 every 0025 ms., whichis one timing period, only at the time when the signal of 103104-1-05 ischanged from 1 to 0 or vice versa. The number of signals of phase 1,produced at the element 102, is equal to the number of impulses of eachdigit dialed by the subscriber. These signals are transmitted to thecounting circuit of Fig. 6 .from .102. On the other hand, the signal 1appearing at 107, which is produced when the dial contact is changedfrom make to break together with the signal appearing at 102, areutilized for the time scaling circuit, which will be explained below andis for detecting the interdigital pause by measuring the duration of themake and the -.duration of the break of dial current. The circuit formedby 108-128 is such a time scaling circuit. The elements 108, 109 and 110are respectively connected to the elements 112, 116 and 120. For an easyunderstanding of the drawing, this connection is shown by R R and RSince the element 108 is an AND element and has a NOT input, 108 assumesa 0 phase when one of the elements 102 and 107 has a signal with phase1, and assumes a phase 1 at other times. Therefore, the signal of 108 is0 during the period .of 0.025 ms., every time the dial contact ischanged from break to make, or vice versa. The signal 109 and 110 isexact- 'ly the same as that of 108, with a slight time :lag. 109 and 110are provided for the purpose of producing a similar signal but with atime difference in the excitation period, in order to control theelements 112, 116 and 117, which have time difierences in theirexcitation periods. When the signal from 108, 109 and 110 is 0,ithesi'gnal of 112, 116 and 120 also becomes 0,'due to the fact that thesignal from 111, and 119 is 0. (This is because, 111, 115 and 119 areAND circuits, and therefore, assume a 0 phase signal, except when thetiming signal is applied to 111.) Then the phase of the loops, ill211311'4, 116--117118, 120121122, becomes 0, irrespective of what phasethese loops :had during the previous stage. When the signal from 108,109 and 110 becomes 1, 112, 116 and 120 act in the same way as an ORcircuit. It will be understood that this is the same as the timingcircuit shown in Fig. 4. The time scaling circuit 111-12S inFig. 5 is abinary counting circuit and counts the timing signals ever 128 ms. 'Itforms a three stage binary counting circuit, and therefore, the signalof the element 123 becomes 1 during the period of 0.025 ms., only whenthe timing signals, 23:8 in-number, are applied thereto. Thus a signalwith phase 1 appears at 123 after a lapse of 102.4 ms. (12.8 ms. 8) froma starting condition of =0 phase of the time scaling circuit. When thissignal appears, the loop 124-1-25 126 takes it and sustains the signal1, and the output from element is 'fed back to 111. Irrespective of thepresence or absence of a timing signal, the phase of the signal of 111is changed to 0, and stops the progress of operation of the time scalingcircuit. If the signal of 102 or 107 becomes 1, prior to the lapse of102.4 ms. after the signal 'of the time scaling circuit returns to 0,such signal 1 from 102 or 107 makes the signal of 108, 109 and 110 0,and returns the time scaling circuit 111-123 to 0 phase, irrespective ofwhat phase condition the said time scaling circuit was taking. Atthenext timing signal, the counting is re-started automatically. In thiscase, the signal 1 does not appear at 123. This means that the durationof make or break of the dialcontacts is less than 102.4;ms. The above102.4'ms. is a time duration which we selected in View 'of the speed ofthe present day telephone set, and therefore, the above time durationcan be chosen at will by an engineer. The signal 1 appearing 'at 123 isapplied to 127 and 128. Since 127 and 128 are both AND elements, thesignal 1 appears at 127 for a period of 0.025 ms., 103 is producing 'a 1signal. The sigial .1 from 103 indicates the state of make of a dialcontact, and the signal 1 from 123 indicates the state continued formore than 102.3 ms., and therefore, such state can show an interdigitalpause. The signal 1 appearing-at 127 is applied to the elements 154 inFig. 6 and 161 :in-Fig. 7. When the signal from 103 is 0, namely, when102.3 ms. has elapsed after the break of the dial current by thesubscriber, the signal 1 appears at 128. This shows that the make andbreak cycle of dialing has stopped. By a timing scaling circuit as aboveexplained, the "durations of make and break of dial contact can .becorrectly counted. In the above example, the durations *of'mak'e andbreak of dial contact can be chosen between 12.8 ms. and 102.4 ms. Thismeans that the dial-speed and the ratio of duration of make and breakcan vary widely,

and therefore, no precise mechanism is necessary for the phone dials.This makes the cost of production much less and makes it unnecessary tochange dials due to their speed variation, the said speed variationconstituting the greater part of the troubles occurring in thepresent-day telephone apparatus.

The circuit shown in Fig. 6 is similar to the binary counting circuit inFig. 5. Compared with the circuit of Fig. 5, that of Fig. 6 is formed inthe same way as far as the elements 131-446 are concerned. The only dif-7 When the phase of the signal of two of the three loops, 136-131-138,140141142 and 144--145-146, is 1, the phase of the signal of 147 becomes1, and the element 135 is converted substantially from an AND elementinto an OR element.

Due to this when the next signal is applied to the counting circuit asinput, the same state as 'if two input signals were received isintroduced. The element 148 produces a signal with phase 1 only whennone or one of the four loops, 132133134, 136137-138, 148141-142, and144-145-146, has a signal of phase 1. The result obtained by countingthe dial impulses in accordance with the above is shown in the followingTable III:

TABLE III Number of impulses Loop 132-133- Loop 140-141- Loop 136137 138Loop 144-145- Element 148 The above table shows that two loops (orelements) have a phase 1 and the other three loops (or elements) have aphase at every number of impulses (two out of five). Thus the decimaldigits 1-l0 are each represented by one of the above binary signals, twoout of five. Such a binary signal will, as is well known, be useful fordetecting troubles during the subsequent operations. It will beunderstood that the counting of dial impulses by the two out of fiveform of signal is much easier than by the hitherto used relays,electronic tubes, etc. The elements, 154, 155, 156, 157, 158 and 159,change the phase of each loop to 0, to make each loop ready for thecounting of the following digit, after the circuit of Fig. 6 hastransmitted the counted digits to the circuit of Fig. 8.

Fig. 7 shows the case of a seven digit system (oflice number 3 digitsand subscriber number 4 digits), and is similar to the above countingcircuit. The number of digits dialed is represented as a binary signalby three loops, 162--163164, 166-167168 and 170171 172. The signalappearing at each loop, after dialing of By the logical product (socalled AND) of three such loops, the elements 182-188 will take thefollowing signal: Directly after the dialing of the hundreds digit ofthe oflice number, 182 assumes phase 1 for a short time, (0.025 ms.) andafter the dialing of the tens digit of the oflice number, 183 assumesphase 1. Upon dialing the thousands, hundreds, tens and units digits ofthe subscribers number, 184, 185, 186, 187 and 188 respectively assumethe phase 1 for a short time. These signals 'drive the parametrons201207 respectively through the vacuum tubes V V in the storing circuitin Fig. 8.

' The elements, 179, 180 and 181, are for restoring the counting circuitwhen such elements receive the signal from 128 and the signal of themarker (from the terminal u), on the giving-up of subscribers dialing oron the completion of the desired connection with the called subscriber.V

Thirty-five elements, M M12, M in Fig. 8 are minute ferrite cores(diameter, about 2 mm.) having magnetic hysteresis. Two lead wires whichare perpendicular to each other pass through each of the above cores.The parametrons appearing at the left side of Fig. 8, 149, 150, 151, 152and 153, are respectively coupled with M 71 12 '12 M1a' 7s 14 74 311dM15 "M75, and the parametrons at the center of Fig. 8, 201, 202, 207,are respectively coupled with M -M M12M25, M17-M75. 1118 parametrons,have a frequency of oscillation, which is half of the oscillationfrequency of the parametrons, 149-153. Parametrons 201207 are excited bythe current which is obtained by amplifying respectively the outputs g gg; of elements 182, 183, 188 in Fig. 7 by means of the left half ofvacuum tubes, V V V For such excitation, the oscillating currents fromparametrons 182188 are applied to the grids, of vacuum tubes only whenthe signals g from 182 188 have a phase 1, and are not applied when thesignal g from 182 188 have a 0 phase. This is accomplished bysuperposing currents of other parametrons having a 1r phase on theoscillating current g from parametrons 182, 183 188. Therefore,parametrons 201, 202, 207 are excited only when the signals from 182,183, 188 have a phase 1, and are not excited at any other time. Directlyafter the dialing of the hundreds of the ofiice number by thesubscriber, 201 is excited by the exciting current having a frequency 1.At this moment, a current having frequency f/2 flows in the secondaryresonance circuit of 201. This current passes through the cores, M M andmagnetizessuch cores with frequency f/ 2. The elements, 149153 oscillateat O-phase or 1r-phase with frequency f. Therefore, when the current ofparametrons 149-153 and 201 is chosen properly, cores of M M areunsymmetrically magnetized, by reason of the superposition of a currentwith frequency f/2. from 207 on a current of frequency f and with 0-phase or 1r-phase from 149153, as shown in Fig. 8a. Thus, either one ofthe two states of residual magnetisation which may be present in aferro-magnetic substance such as a ferrite core is placed in the core.This residual magnetism remains, even after the removal of themagnetisation currents, due to the oscillation current of 201. Which ofthe two kinds of residual magnetism remains depends upon whether thesignal fi'om the parametrons 149, 153 has a phase of 0 or 1. Similarly,when 202 is excited (directly after the dialing of tens of the oflicenumber), the signal from 149153 is sustained in cores M M as residualmagnetism. The same operation is repeated thereafter. Namely, the unitsof the ofiice number, and the thousands, hundreds, tens and units of thesubscribers number are stored respectively in al- 35, 41 45 51* 55,MST-M65 and M71 M The operation all carried out in the form of two outof five code. In this way, all the digits are 'stored in M M- The storedsignal information (ofiice number and subscribers telephone number) canbe read in the following way: The signal g g g, is applied to the righthalf of each of vacuum tubes V V through the terminals, S S of Fig. 9.By means of such a current having frequency f, amplified by the vacuumtubes, V V the parametrons 201 207, are again excited, and the currenthaving frequency f/2 is produced in each of such parametrons. We shallexplain the case where the current having frequency f/2 is produced at201. The produced current passes through the magnetic cores M M M Sincethe magnetic cores have non-linear properties, a voltage havingfrequency f, the second harmonic of f/2, is produced in reading can bemade when the parametrons, .202, 203,

205, 206 and 207 are successively excited. Therefore, :parametrons'196200 are successively excited during the succeeding exciting .periodHI, and oscillate in phase with the harmonics produced in each core.Thus, the-stored information can be read. The information of each coreremains even attertlrezabovezreading. However, the dem'agnetisationthereof is :not necessary, because such remaining information isamalgamated with the succeeding information which is written at the nextdialing.

In the example of-Figss6 and 8ythe counting and storing of digits dialedare carried out separately. The counting is done by the circuit of Fig.6, and the storing is accomplished by using one core for each bit ofinformation as shown in Fig. 8. The storing of the telephone number ofthe subscriber by using small magnetic cores, is stable and inexpensive.

It must be understood that the above explanation of the circuits of adial impulse register is not to be limited to the examples shown. Othersystems of counting, such as a conventional binary decimal code, decimalcode and bi-quinary code, (all based upon a binary code) can be used ina manner similar to the above-mentioned two out of five binary code.

Fig. 11 shows the counting circuit in which the conventional binary codeis used. The connection of parametrons is similar to that shown in Fig.5, the only difierence being that a single parametron 301 replaces theAN element 111 in Fig. 5. Therefore, the circuit of Fig. 11 is alwaysready for counting of digits by dial impulses. The operation of thiscircuit is also quite similar to that of Fig. 5. It will be clear thatthe relation between the dial impulses and this circuit can berepresented as in the Table V.

TABLE V Number oi Loop Loop Loop Loop impulses 302-303-304 306-307-308310-311-312 314-315-316 No 0 0 0 1 1 0 O 0 2 0 1 0 0 3 1 1 0 0 4 0 0 1 0l5 1 0 1 0 6 0 1 1 0 7 1 1 1 0 8 0 0 0 1 9 1 0 0 l 10=0 0 1 0 1 Fig. 12shows the counting circuit in which the biquinary code is used. Thecircuit has six output terminals, I, 2, 3, 4, 5n and V of which u1 n5nassume phase 1, when a number of impulses 1 and 6, 2 and 7, 5 and 10 arerespectively applied to the input of Fig. 12 and assume phase 0, atother times. At the terminal V," a signal of phase 1 appears when 6 ormore than 6 impulses are applied, and a signal of phase 0 appears when 5or less than 5 impulses are applied. To R, which is connected to theparametron 528, a signal of phase 1 is normally applied, and a 0 phasesignal is applied only when the circuit is restored for the nextoperation. Once the phase of the signal of 528 is made 0, the phase ofthe signal of all the elements, 501-527, is returned to 0. Thereafter,502, 505, 525, operate as if these were OR elements. In this state, whena signal is applied to the upper input terminal, the said signal isapplied to 507, 501, 508, 511, 527. All the elements assume a 0 phase,except the AND element, 507, which assumes phase 1. When 507 assumesphase 1, 505 also assumes phase 1, due to an OR operation, and the loop504-505-506 also assumes phase 1. At the same time, the loop,501-502-503, also assumes 10 phase 1. When the :second signal is appliedat therinput terminal, 511 assumes a .phase :1 i011 zreceiving thei'nputsignal :and makes thephase of 508-509-510 31311383 :1, due to :the:application of :the signal -of phase l from 506 to 511. 0n the otherhand, 504 assumes 1phase0 and areturns 504-505-506 to fphaseit), due :10theapplication of the signal ofa phase opposite .t'o-theqahase'of theinput to 504. Similarly, when the .third (signal is applied, 5L2-5l3-5l4assnmes phase 1 and 508-509-510 returns to phase 0. When the fourthsignal is applied, 516-517-518 assumes phase :1 and 51-2-513-5-14=1'eti1rns tophaseiO. When =the;fiftheignal is apfplzied, 520-52-1=;522assumes phase 1, and 501-502-503 'is iorcedphase :return to 0, by afeed-back coupling -from:522. the sixth signal isapplied,=524-525-526eassumesiphase liand 504-505-506 again assumesphase 1. When the seventh and higher signals and so are applied, similaroperations are repeated, except that the last loop, 524-525-526, staysat phase 1. The relation between the dial impulses and the operation ofeach loop is shown in the Table VI.

TABLE VI loop 504- 505-506 loop 508- 509-510 loop 512- 513-514 loop 516-517-518 loop 520- coccioose- O OQOHCQOOHO C QQHODQOHOO a OHOOOOWOOO OHQDOOI-IQOQO c b-H-H- HHOQOQO 0 It will be understood that a decimalcounting circuit can be made easily. This is done by connecting, to 524,similar circuits to those which follow 504, shown in Fig. 12.

Similarly, any kind of counting circuit can be formed in a simple way,by using parametrons as operating elements.

We claim:

1. A dial impulse register for an automatic telephone exchange,comprising a means for converting the dial current into a high frequencyalternating current having one of two phase states, a measuring anddetecting means connected to said converting means for measuring theduration of said phase states of the said high frequency alternatingcurrent and detecting the dial impulses and lapse of time between thedial current impulses corresponding to one dial digit and thosecorresponding to the succeeding dial digit, a counting means connectedto said measuring and detecting means for counting dial current impulsesdetected by said measuring and detecting means, and a storing meansconnected to said counting means for storing the number of dial currentimpulses thus counted, said measuring and detecting means and saidcounting means respectively comprising circuits composed of resonatorshaving non-linear reactance elements as a part thereof whereby there canbe performed a logical operation utilizing the two possible phase statesof the oscillation of said resonators as logical elements.

2. A dial impulse register as claimed in claim 1 in which said means forconverting comprises resonator means having a non-linear reactanceelement for producing a high frequency alternating current, and meansfor applying said dial current impulses to said resonator means forchanging one of the possible phase states of said resonator means to theother possible phase state in response to the make and break of dialcurrent.

3. A dial impulse register as claimed in claim 1 in which said means forconverting comprises resonator 1 1 means having a non-linear resistanceelement for producing a high frequency alternating current, and meansfor applying said dial current impulses to said resonator means forchanging one of the possible phase states of said resonator means to theother possible phase state in response to the make and break of dialcurrent.

4. A dial impulse register as claimed in claim 1 in which said means forcounting comprises resonator means for counting the number of breaks inthe dial current in the form of a binary decimal code.

5. A dial impulse register as claimed in claim 1 in which said means forcounting comprises resonator means for counting the number of breaks inthe dial current in the form of bi-quinary code.

6. A dial impulse register as claimed in claim 1 in 12 which said'meansfor counting comprises resonator means for counting the number of breaksin the dial current in the form of a two out of five binary code.

7. A dial impulse register as claimed'in claiml in which said means forstoring'comprise a plurality of ferro-magnetic cores, means for imposingon each of said cores a plurality of high frequency alternating currentseach having a phase depending on the numbers dialed, means forsuperimposing on said cores a current having a frequency one-half thatof said high frequency current, whereby each of said cores aremagnetized unsymmetrically to one of the two states of residualmagnetism inherent in said cores.

i No references cited.

